The big news for those making predictions: More than 70,000 more mail-in votes had been cast by registered Democrats than by registered Republicans.

That could give a big leg up to Democrats in12 Congressional Races and New Jersey Senate Race — several of which are being closely watched nationwide, with predictions of a "Blue Wave" in the House building confidence. In New Jersey alone, some predictions estimate the state could be down to a single Republican representative before the night is out.

It's particularly good news for Senate incumbent Democrat Robert Menendez, whose candidacy was marred by a 2017 corruption federal trial, and who has faced tough competition from Republican Bob Hugin — putting the half-century Democratic hold on the seat in question.

Republicans haven’t won a Senate race in New Jersey since 1972, but as polls tightened and Hugin’s financial advantage piled up, analysts at the Cook Political Report shifted their rating of New Jersey’s Senate race to a toss-up on Oct. 26. Other analysts have said Menendez remains favored — but polls never showed and clear preference for Hugin. The mail-in advantage for Democrats could be enough to secure Menendez's lead once and for all.

This is the first year New Jersey's operating under a law that automatically established residents as mail-in voters if they'd previously voted as such in 2016 and 2017. The law, signed by Murphy over the summer, led to some confusion at the polls — since anyone on the books as a mail-in voter (including those who didn't expect to be) could only fill in a provisional ballot, to be counted after verification they hadn't voted by mail already.

Vote-by-mail ballots that are received by county officials as late as 8 p.m. Thursday, 48 hours after the polls close, must be counted if they’re postmarked by Tuesday. In the past, anything that arrived after Election Day was labeled as too late and the voters notified their ballot didn’t count.

And that's led to questions over whether many races will still be too close to call on Election Night — with an unknown amount of ballots yet to come back.

“I believe that it’s going to be a little dicey,” said Monmouth County Clerk Christine Giordano Hanlon. “I hope that it won’t be, but with close races, I think that there’s the potential that we will not have election results in many cases on election night.”